I have mushroom card:
type: custom:mushroom-template-card
entity: heater_entity
icon: mdi:radiator
icon_color: |
{% if is_state('heater_entity', 'on') %}
green
{% else %}
gray
{% endif %}
primary: heater
tap_action:
action: toggle
secondary: ''
how can I add as a second line time count down in seconds?
in automation YAML I have define 600 seconds
00:10:00
00:09:59
00:09:58
etc…
Thanks